package com.code.springboot.common;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

import com.code.springboot.common.R;

import javax.servlet.Servlet;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * @program: springboot
 * @create: 2022-08-10 14:29
 **/

@RestController
@RequestMapping("/common")
public class CommonController {
    @Value("${reggie.path}")
    private String basePath;

    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是临时文件，需要将该文件转存到指定位置，否则请求完成后，临时文件会删除。

        //获取原文件名字
        String  originalFilename = file.getOriginalFilename();

        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用uuid生成文件名，防止文件重名引起文件覆盖
        String fileName = UUID.randomUUID().toString() + suffix;

        //创建目录
        File dir = new File(basePath);
        if(!dir.exists()){
            dir.mkdirs();
        }


        try {
            file.transferTo(new File(basePath + fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }


        return R.success(fileName);
    }


    //文件下载
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){

        try {
            //输入流，通过输入流读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));


            //输出流，通过输出流将文件写回浏览器，展示页面
            ServletOutputStream outputStream =response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }

            //关闭资源
            outputStream.close();
            fileInputStream.close();

        } catch (Exception e) {
            e.printStackTrace();
        }



    }
}
